Speaking to reporters on a campaign swing to back Murray Rankin’s run in a Nov. 26 by-election, Mulcair said the Conservative government’s proposed exemption of most lakes and rivers from federal environmental scrutiny is added to earlier changes that weaken the process too much for it to be reliable.

Both Mulcair and B.C. NDP leader Adrian Dix have strongly opposed Enbridge’s Northern Gateway oil pipeline planned from Alberta to Kitimat. Dix has refrained from making a similar call on Kinder Morgan’s proposal to twin the TransMountain pipeline from Edmonton to Burnaby. But Mulcair said there is no way such an expansion could proceed with the rules the way they are.

“To the extent that you can’t even discuss these things in the absence of a thorough, credible, complete assessment process, you can’t therefore even discuss an increase in flow and an increase in tanker traffic, because the condition is carrying out a thorough examination,” Mulcair said. “And the Conservatives have gutted that. They’ve rendered it meaningless.”

Rankin, a lawyer who advised the B.C. NDP on its plan to withdraw B.C. from the joint review of Northern Gateway, is running in a by-election to replace retired Victoria MP Denise Savoie. Rankin agreed with Mulcair that the Kinder Morgan proposal shouldn’t proceed with the current system, adding that there has not yet been a formal application for the TransMountain expansion.

Mulcair said the most damaging change is making assessments subject to cabinet approval, so even if an expert panel rejects a project, it can be overruled.

Prime Minister Stephen Harper has insisted that Northern Gateway and other projects will still be approved or denied on scientific grounds only.

When federal Transport Minister Denis Lebel announced changes to the Navigable Waters Protection Act in October, he said the 1882 legislation had greatly overextended its original intent. Lebel cited a lake near Edmonton that required 80 separate federal assessments to build boat docks for cottages.

Other environmental laws still apply to protect lakes and rivers, whether they are navigable or not, he said.